The triple beam balance<span> is used to </span>measure<span> masses very precisely; the reading error is 0.05 gram.</span>
Answer:
10.78 → 4 significant figures, pH = 10.78 → [H⁺] = 1.66ₓ10⁻¹¹ M
6.78 → 3 significant figures, pH = 6.78 → [H⁺] = 1.66ₓ10⁻⁷ M
0.78 → 2 significant figures, pH = 0.78 → [H⁺] = 0.166 M
pH always can be expressed by at least 4 significant figures. The [H⁺], can be expressed by, at least 3 significant figures
Explanation:
Significant figures are the numbers of a measurement that have certainty plus a doubtful number (it is associated with the uncertainty in the measurement). For example, if we measure a paper with a ruler and the ruler measures up to centimeters we can say that the paper is 7.5 cm long, with which we know that the paper is 7 cm + 0.5 cm which we associate with uncertainty. In this case we talk about two significant figures. If the sheet measured 7.57 cm we would already be talking about a more precise measurement and in this case with 3 significant figures.
10.78 → 4 significant figures
6.78 → 3 significant figures
0.78 → 2 significant figures
To determine [H⁺], we apply 10^-pH
10⁻¹⁰°⁷⁸ = 1.66ₓ10⁻¹¹ M
10⁻⁶°⁷⁸ = 1.66ₓ10⁻⁷ M
10⁻⁰°⁷⁸ = 0.166 M
Answer:
1) Basic
2) Basic
3) Acidic
Explanation:
pH of a solution is a measure of the H3O+ ions in the solution and hence reflects its acidity.
![pH = -log[H3O+]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH3O%2B%5D)
Solutions are classified as acidic, basic or neutral based on the pH range
-pH < 7, acidic
- pH = 7, neutral
- pH > 7, basic
1) [H3O+] = 2.5*10^-9M
![pH = -log[H3O+]=-log[2.5*10^{-9}]=8.60](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH3O%2B%5D%3D-log%5B2.5%2A10%5E%7B-9%7D%5D%3D8.60)
Since pH > 7, solution is basic
2)[OH-] = 1.6*10^-2M
![pOH = -log[OH-]=-log[1.6*10^{-2}]=1.80](https://tex.z-dn.net/?f=pOH%20%3D%20-log%5BOH-%5D%3D-log%5B1.6%2A10%5E%7B-2%7D%5D%3D1.80)
pH = 14 - pOH = 14 - 1.80 =12.2
Since pH > 7, solution is basic
3) [H3O+] = 7.9*10^-3M
![pH = -log[H3O+]=-log[7.9*10^{-3}]=2.10](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH3O%2B%5D%3D-log%5B7.9%2A10%5E%7B-3%7D%5D%3D2.10)
Since pH < 7, solution is acidic
Answer:
<span>The energy required to go from liquid to gas is called as Latent Heat of Vaporization.
Explanation:
The process of conversion of liquid into gas phase is known as vaporization while the conversion of gas into liquid state is called as condensation. The liquid having stronger intermolecular forces than gases require some energy to break those interactions hence, the heat provided to break these interactions and convert it into gas phase is called as heat of vaporization. Remember, heat of vaporization and heat of condensation are same for a given substance but with different signs.
Example:
Heat of Vaporization of Water = 40.65 kJ/mol
Heat of Condensation of Water = - 40.65 Kj/mol</span>
Answer:
Explanation:The Î""G°′ of the reaction is −7.180 kJ·mol−1. Calculate the equilibrium constant for the reaction at 25 °
